Filters and filter assemblies are commonly used in applications where a liquid needs to be cleaned of particulate matter larger than a certain predetermined size. For example, in gasoline powered engines, a filter assembly may be used to remove particulate in the fuel that would otherwise clog and adversely affect the efficiency of the engine. The fuel filter assembly may have a first stage filter that removes larger particulate from the fuel and a second stage filter that removes smaller particulate from the fuel prior to the fuel being delivered to the engine. A typical vehicle fuel delivery system includes a fuel tank, a fuel pump, a fuel filter assembly and fuel lines through which the filtered fuel is pumped to the vehicle engine. The first stage fuel filter may be attached to an inlet of the fuel pump so that the fuel passes through the first stage filter immediately prior to entering the fuel pump. The filtered fuel is then pumped from the fuel pump to the second stage fuel filter which removes finer particulate from the fuel. The fuel then travels through a fuel line leading to the engine. A fuel regulator is also usually provided to control fuel pressure in the fuel line.
A mounting platform may be used upon which the fuel pump and fuel filters are mounted, the combination of which is typically referred to as a “fuel module”. The mounting platform and components thereon are then inserted through an opening in the fuel tank to position the components within the fuel tank. The mounting platform is firmly secured to the tank and seals the opening closed. Should the fuel delivery components within the fuel tank need servicing, the mounting platform is simply detached from the tank and removed along with the fuel delivery components mounted thereto.
The dimensions of the fuel tank and the fuel delivery components described above varies according to the requirements of the vehicle design. A fuel delivery system for a motorcycle is therefore very different than a fuel delivery system for an automobile. A motorcycle requires much smaller fuel delivery system components and this is a critical design consideration of a motorcycle fuel delivery system designer. Thus, the various fuel system components must be designed with the specific space requirements of the vehicle application in mind. Other equally important design considerations include ease of assembly and positioning of the components for optimum effectiveness. For example, the fuel filter is a porous material whose effectiveness is directly correlated to its surface area and placement within the fuel tank. The larger the surface area, the more fuel is strained therethrough. Likewise, the more of the filter that is submerged in the fuel (whose level continuously changes between full and near empty), the more of the filter is utilized in straining the fuel and its effectiveness is thus optimized. While fuel filters have been designed with the forgoing in mind, there remains a need for a fuel filter, particularly for small fuel tank applications, whose assembly is relatively simple and includes features which automatically position the filter in the tank for optimum effectiveness.